I think the yellow is normal for the resin. It turns out that getting a tank hydrotested locally is a major pain, and shipping to crossfire is a way better method. Also, all this time, I never knew that the full name was "hydrostatic testing". I'm trying to get Taylor (phatphil) to come play in this 3man mech/pump (1 electric item per team, ours is going to be an LV1 with shake hopper) tournament with my friend and me.